Leica Biosystems PELORIS_PELORIS II - Manual (Page 150)

Troubleshooting
Leica PELORIS™ User Manual Rev K © Leica Biosystems Melbourne Pty Ltd 2011 150

20 mL 5% sodium carbonate

Ethanol-glycerol

90 mL 60% ethanol

10 mL glycerol
Then process tissue normally.
4. Hard Shriveled Tissue – Dried Out but Processed Through to Wax
Remove wax and rehydrate as detailed in problem 6, below. Apply a reconstitution solution as
described in problem 3.
5. Tissue Insufficiently Infiltrated with Wax
Place the cassettes back into the wax bath with vacuum and stirrer on and temperature at 65 ° C.
This may be necessary when tissue has been prematurely removed from the wax.
6. Adequately Fixed Under-processed Tissue
This problem can be due to too short a protocol, too large a specimen, or processor failure. Four
methods are recommended, but first identify the problem and rectify it. Test your fix by running
control tissue through the processor before reprocessing the patient tissue (or use another
processor).
For all the following solutions first melt down the blocks, blot off excess wax, and then place the
specimens in new cassettes. This minimizes wax contamination of the processing reagents.
A. Taggart’s Method
Place the cassettes into a beaker of isotonic saline (aqueous solution of 0.9% sodium chloride) in
an incubator at 65 °C for 1 hr. The wax rises to the surface. Remove the tissue and reprocess from
formalin using a protocol suitable for its size and nature (see 8.2.1 Specimen Type and Protocol
Duration).
The saline gently rehydrates the tissue, which can then be processed normally. Saline is a non-toxic
reagent that can be safely used in an open laboratory.
B. Rapid Reverse Process
Process using a fast modified cleaning protocol (see Rapid Reverse Cleaning Protocol below). Do
not use the default Quick Clean protocol or protocols derived from this, because they finish with a
drying step that will damage the tissue. After the cleaning protocol reprocess from formalin using a
schedule suitable for the size and nature of the specimen (see 8.2.1 Specimen Type and Protocol
Duration).
Processor cleaning reagents provide a convenient automated method to remove wax and take the
tissue back to alcohol. It is however, a potentially harsher method than methods A or C.